An embedded system is a specialized computer in which operating system and application functions are often combined into the same program. Generally, an embedded system implies a fixed set of functions programmed into a non-volatile memory (ROM, flash memory, etc.) in contrast to a general-purpose computing machine.
Embedded systems are growing more and more complex, requiring a range of external management applications such as SNMP, Command Line Interfaces, TNM, WBEM, etc. These applications have completely different interfaces, network protocols and purposes but must all interface to the low-level internals of the embedded system.
In order for an embedded system to perform successfully in an environment, it is necessary that the embedded system be configured to operate as desired for troubleshooting and monitoring purposes. Further, the embedded system needs to be able to provide its current configuration or restore to a saved configuration when requested. This functionality is collectively known as “management” of the embedded system.
Management of the embedded system may be effected through a variety of user interfaces. The most common is Command Line Interface (CLI), where configuration and display commands are entered in text mode and promptly executed. Another common interface is Simple Network Management Protocol (SNMP) where configuration and monitoring data is transmitted over the network.
Prior technology for implementation of command line user interfaces relies on a set of closely coupled functions between the commands defined and the application functions or services of the embedded system. Typically a set of function calls is provided by the embedded system and utilized in the implementation of the CLI. This leads to a dependency of the user interface application on the underlying implementation of the embedded system which requires the embedded system services to provide a consistent interface to the CLI.
Since the user interface application and the application functions (or services) in the embedded system are inextricably linked through this functional interface (i.e., function calls), this leads to a brittle code structure that is not easily extended, difficult to manage and maintain. It would be advantageous to have a method that provides a generalized user interface to an embedded system in such a way that the generalized user interface is decoupled from the services and features delivered and implemented in the embedded system.